U.S. training efforts with members of the Malian military over the last several years led to some “very worrisome” results, said U.S. Army Gen. Carter Ham.

The French government sent troops to Mali in mid-January at the request of a government struggling to thwart the advance of Islamist and foreign rebels.

Ham, leader of the U.S. Africa Command, said at Howard University in Washington that mistakes were made during a U.S.-Malian military training program. Capt. Amadou Sanogo, who led a military coup in early 2012, was trained by U.S. military forces.

“(This is) very worrisome for us,” he was quoted by the Defense Department’s news service as saying.